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Resumen La neurofibromatosis tipo 1 o enfermedad de von Recklinghausen es una enfermedad genetica, progresiva y multisistemica que afecta predominantemente a la piel y el sistema nervioso. La alteracion vascular es poco frecuente pero puede tener resultados catastroficos. Las pacientes gestantes afectas de esta enfermedad necesitan un seguimiento exhaustivo y multidisciplinar con el objetivo de controlar las posibles alteraciones vasculares sobre todo renales por ser las mas frecuentes. Presentamos el caso de una paciente diagnosticada de NF-1 que presento un hemoperitoneo masivo espontaneo en el postoperatorio tardio de una cesarea electiva. El sangrado espontaneo de grandes vasos es una rara pero potencial complicacion letal que puede producirse en pacientes afectos de neurofibromatosis I y que puede precisar de tratamiento quirurgico urgente.

Resumen Introduccion El esfinter urinario artificial (EUA) no esta extendido en el tratamiento de la incontinencia urinaria de esfuerzo (IUE) femenina debido a la baja reproducibilidad de las tecnicas empleadas. Describimos un nuevo abordaje de implante laparoscopico, cuyo paso fundamental consiste en disecar el espacio vesicovaginal. Esto permite una aproximacion bajo vision directa a la cara posterior del cuello vesical. Material y metodos Presentamos dos casos realizados con esta aproximacion. Se realiza un abordaje transperitoneal en posicion de Trendelenburg. Los principales pasos son: creacion del espacio vesicovaginal hasta identificar el cuello, creacion de dos espacios laterovesicales, comunicacion de los mismos con el espacio vesicovaginal y diseccion de la cara anterior del cuello intentando preservar el ligamento pubovesical. El manguito y reservorio se introducen a traves del trocar infraumbilical de 12 mm. Por una incision suprapubica izquierda se externalizan las conexiones y se crea un tunel subcutaneo hasta el labio mayor, donde se coloca la bomba de activacion. Finaliza el procedimiento con el cierre del peritoneo. Es fundamental la utilizacion de una valva vaginal para facilitar la diseccion. Resultados Tiempo quirurgico: 140 y 135 min, sin complicaciones intraoperatorias. Tras la retirada de la sonda vesical una paciente presento residuo posmiccional elevado que se manejo de forma conservadora. Estancia hospitalaria: 72 h. A los 3 y 9 meses, las pacientes presentaron continencia total. Conclusiones Presentamos resultados preliminares de implante laparoscopico de EUA mediante la aproximacion vesicovaginal a la cara posterior del cuello, que podria disminuir las potenciales complicaciones observadas con las tecnicas habituales.

Introduction The artificial urinary sphincter (AUS) is not used extensively in the treatment of female urinary stress incontinence (USI) due to the poor reproducibility of the techniques used. We describe a new approach to laparascopic implantation, of which dissection of the vesicovaginal space is an essential step. This enables an approach under direct vision to the posterior surface of the bladder neck. Material and methods We present two cases where this approach was used. A transperitoneal approach was made in the Trendelenburg position. The main steps were: creating the vesicovaginal space until identifying the bladder neck, creating two laterovesical spaces, communicating these with the vesicovaginal space, and dissecting the anterior surface of the bladder neck, attempting to preserve the pubovesical ligament. The cuff and reservoir were inserted through the 12 mm infraumbilical trocar. The connections were externalized through a left suprapubic incision and a subcutaneous tunnel created up to the labia majora where the activation pump was placed. The procedure was completed with closure of the peritoneum. It is essential to use a vaginal valve to facilitate dissection. Results Surgery time: 140 and 135 min, with no intraoperative complications. After removing the urinary catheter, one patient had elevated postvoid residual urine volume, which was managed conservatively. Hospital stay: 72 h. At 3 and 9 months the patients were fully continent. Conclusions We present the preliminary results of laparoscopic implantation of an AUS through a vesicovaginal approach to the posterior surface of the bladder neck, which might reduce potential complications that have been observed after the routine techniques.

Pancreatic cancer (PC) is a highly fatal cancer with currently limited opportunities for early detection and effective treatment. Modifiable factors may offer pathways for primary prevention. In this study, the association between the Healthy Lifestyle Index (HLI) and PC risk was examined. Within the European Prospective Investigation into Cancer and Nutrition cohort, 1113 incident PC (57% women) were diagnosed from 400,577 participants followed-up for 15 years (median). HLI scores combined smoking, alcohol intake, dietary exposure, physical activity and, in turn, overall and central adiposity using BMI (HLIBMI) and waist-to-hip ratio (WHR, HLIWHR), respectively. High values of HLI indicate adherence to healthy behaviors. Cox proportional hazard models with age as primary time variable were used to estimate PC hazard ratios (HR) and 95% confidence intervals (CI). Sensitivity analyses were performed by excluding, in turn, each factor from the HLI score. Population attributable fractions (PAF) were estimated assuming participants’ shift to healthier lifestyles. The HRs for a one-standard deviation increment of HLIBMI and HLIWHR were 0.84 (95% CI: 0.79, 0.89; ptrend = 4.3e−09) and 0.77 (0.72, 0.82; ptrend = 1.7e−15), respectively. Exclusions of smoking from HLIWHR resulted in HRs of 0.88 (0.82, 0.94; ptrend = 4.9e−04). The overall PAF estimate was 19% (95% CI: 11%, 26%), and 14% (6%, 21%) when smoking was removed from the score. Adherence to a healthy lifestyle was inversely associated with PC risk, beyond the beneficial role of smoking avoidance. Public health measures targeting compliance with healthy lifestyles may have an impact on PC incidence. © 2019, Springer Nature B.V.

Neurofibromatosis type 1 (NF-1) or von Recklinghausen's disease is a genetic, progressive, multi-system disease that predominantly affects the skin and nervous system. Vascular involvement is rare, but can have catastrophic results. Pregnant patients with this disease need careful, multidisciplinary follow up in order to control possible vascular alterations, which usually affect the kidneys. We present the case of a patient diagnosed with NF-1 who debuted with massive spontaneous hemoperitoneum in the late postoperative period of an elective Cesarean section. Spontaneous bleeding from large vessels is a rare but potentially lethal complication that can occur in patients with NF-1, and may require urgent surgical treatment. (C) 2020 Sociedad Espanola de Anestesiologia, Reanimacion y Terapeutica del Dolor. Published by Elsevier Espana, S.L.U. All rights reserved.

Context and objective The increasingly early diagnosis of prostate cancer requires a search for therapeutic alternatives with good oncological results that in turn facilitate a good long-term quality of life. This review analyses 2 minimally invasive therapies for treating localized prostate cancer in terms of oncological and functional results, as well as the complications resulting from the therapies. Acquisition of evidence A systematic literature review was conducted of the treatment of localized prostate cancer with 2 ablative techniques as the primary therapy: cryosurgery or cryotherapy and high intensity focused ultrasound (HIFU). We included patients who underwent procedures that included the entire gland, with hemiablation or focal therapy, which were indicated for low to intermediate-risk prostate cancer according to the D’Amico criteria. We excluded patients with high-risk prostate cancer and those who underwent any prior treatment for prostate cancer. Synthesis of the evidence After conducting the literature search and excluding the studies that did not meet the protocol criteria, we reviewed a total of 14 studies, with a total of 350 patients treated using cryotherapy and 1107 treated with HIFU. All studies were either prospective or retrospective and were not randomized. The patients’ mean age was younger than 75 years. Overall, the rate of disease recurrence in the patients treated with cryotherapy varied between 13.2% and 26%, while the rate for those treated with HIFU varied between 7.3% and 67.9%. The overall demonstrated continence at 12 months was 97.6–100% for cryotherapy and 96–100% for HIFU. In terms of sexual potency rates, cryotherapy showed complete potency at 12 months for 86–100% of the patients treated with focal cryotherapy and slightly lower rates for hemiablation (76.9–100%) and total therapy (39%). HIFU showed potency rates of 89%, 52–80% and 33–78% for focal therapy, hemiablation and total therapy, respectively. Conclusions Both techniques have comparable functional results, although the somewhat poorer oncological results for HIFU reflect a steeper learning curve, which could lead to its use in centers with high volumes of patients.

Resumen Contexto y objetivo El diagnostico cada vez mas precoz del cancer de prostata obliga a buscar alternativas terapeuticas con buenos resultados oncologicos, que a su vez faciliten una buena calidad de vida a largo plazo. La presente revision analiza los resultados de 2 terapias minimamente invasivas en el tratamiento del cancer localizado de prostata en cuanto a resultados oncologicos y funcionales, asi como las complicaciones derivadas de los mismos. Adquisicion de la evidencia Revision sistematica de la literatura referida al tratamiento del cancer localizado de prostata con 2 tecnicas ablativas como terapia primaria: la criocirugia o crioterapia y el high intensity focused ultrasound (HIFU). Se incluyen pacientes con procedimientos que incluian la totalidad de la glandula, con hemiablacion o con terapia focal e indicados en cancer de prostata de bajo riesgo o riesgo intermedio segun criterios D’Amico. Se excluyen pacientes con cancer de prostata de alto riesgo, o aquellos que hayan recibido cualquier tratamiento previo para el cancer de prostata. Sintesis de la evidencia Tras la busqueda y exclusion de estudios que no cumplian los criterios del protocolo, se revisan un total de 14 estudios, con un total de 350 pacientes tratados mediante crioterapia, y un total de 1.107 pacientes tratados con HIFU. En todos los casos se trataron de estudios prospectivos o retrospectivos, no aleatorizados. La edad media de los pacientes fue de menos de 75 anos. En global la tasa de recidiva anatomopatologica en los pacientes tratados con crioterapia oscila entre el 13,2% y el 26%, mientras que en el HIFU oscilan entre el 7,3% y el 67,9%. La continencia global mostrada fue de un 97,6-100% en el caso de la crioterapia, y un 96-100% en el HIFU a los 12 meses. Respecto a las tasas de potencia sexual la crioterapia muestra una potencia completa del 86-100% a los 12 meses en pacientes tratados con crioterapia focal, y algo menores en la hemiablacion (76,9-100%) y en la terapia total (39%). El HIFU reporta tasas de potencia del 89% 52-80% y 33-78% en terapia focal, hemiablacion y terapia total respectivamente. Conclusiones Ambas tecnicas presentan unos resultados funcionales equiparables, si bien los resultados oncologicos algo mas pobres en el HIFU son reflejo de una curva de aprendizaje mas complicada, que puede abocar su uso a centros con alto volumen de pacientes.

Resumen: Introducción: La hemorragia peri-intraventricular (HIV) es la complicación neurológica más importante de la prematurez, con alteraciones en el neurodesarrollo a largo plazo. El objetivo del trabajo fue describir los factores de riesgo asociados a la HIV en neonatos

Objectives The objective of this study is to compare direct costs of repairing pelvic organ prolapse by laparoscopic sacrocolpopexy (LS) against vaginal mesh (VM). Our hypothesis is the correction of pelvic organ prolapse by LS has a similar cost per procedure compared to VM. Material and methods We made a retrospective comparative analysis of medium cost per procedure of first 69 consecutive LS versus first 69 consecutive VM surgeries. We calculate direct cost for each procedure: structural outlays, personal, operating room occupation, hospital stay, perishable or inventory material and prosthetic material. Medium cost per procedure were calculated for each group, with a 95% confidence interval. Results LS group has a higher cost related to a longer length of surgery, higher operating room occupation and anesthesia; VM group has a higher cost due to longer hospital stay and more expensive prosthetic material. Globally, LS has a lower medium cost per procedure in comparison to VM (5985.7 € ± 1550.8 € vs. 6534.3 € ± 1015.5 €), although it did not achieve statistical signification. Conclusions In our midst, pelvic organ prolapse surgical correction by LS has at least similar cost per procedure compared to VM.

Resumen Objetivos El objetivo del estudio es realizar un analisis comparativo de los costes directos de la reparacion del prolapso de organos pelvicos mediante colposacropexia laparoscopica (CL) o malla transvaginal (MTV). La hipotesis inicial es que la correccion del prolapso de organos pelvicos mediante CL presentaria al menos un coste por procedimiento similar a la correccion mediante MTV. Material y metodos Analisis retrospectivo comparativo del coste medio por procedimiento de los primeros 69 procedimientos consecutivos de CL frente a los primeros 69 procedimientos consecutivos de MTV. Para cada procedimiento, se determinaron los costes directos: gastos estructurales, personal, ocupacion de quirofano, estancia hospitalaria, material fungible e inventariable y el material protesico implantado. Se determino el coste medio por procedimiento para cada uno de los grupos, con el intervalo de confianza al 95%. Resultados Mientras que el grupo de CL incurrio en un mayor gasto en relacion con un mayor tiempo quirurgico, ocupacion de quirofano y anestesia, el grupo de MTV incurrio en un mayor gasto en relacion con una mayor estancia hospitalaria y un coste mayor del material protesico implantado. De forma global, si bien el grupo de CL presento un coste medio por procedimiento menor que el grupo de MTV (5.985,7 € ± 1.550,8 € vs. 6.534,3 € ± 1.015,5 €), esta diferencia no alcanzo la significacion estadistica. Conclusiones En nuestro medio, la correccion del prolapso de organos pelvicos mediante CL presenta al menos, un coste por procedimiento similar a la correccion del mismo mediante MTV.

The diatom Halamphora coffeaeformis represents an alternative feedstock of oils for the biodiesel production. In addition, its siliceous cell wall (named frustule) presents possible industrial applications that have not been reported in the literature yet. Thus, the main objective of this study was to perform a three-dimensional reconstruction of H. coffeaeformis´ frustule from scanning electron micrographs, in order to have a study model. For this, the biomass of the species growing in a photobioreactor was harvested and treated as follows: a) some samples were dehydrated and subjected to a critical point; and b) other samples were treated with H2O2 in order to analyse the frustule´s ornamental pattern. All samples were metallized with gold, using an Argon plasma metal evaporator (Pelco model3) and they were observed with a LEO Scanning Electron Microscope, model EVO 40 XVP 2004. The frustules were elliptical to lanceolate with protracted ends. Valves presented convex dorsal margin and straight ventral margin. Dorsal striae were biseriate and radiate; ventral striae were short, uniseriate, radiate at the center and convergent at the ends of the valves. The raphe was straight and close to the ventral margin. The micrographs were analysed and separated into layers with the Adobe Photoshop CS6 software. The layers were vectorised with the Inkscape software and loaded and assembled in the Tinkercad software. The final aspects of the digital model were moulded on the page https://stephaneginier.com/sculptgl/. Finally, 3D printing was done with a CoLiDoTM 3.0 L printer, obtaining a three-dimensional replica representative of the H. coffeaeformis´ morphology . This replica will serve as a model for studies of its frustules related to nanotechnology and /or catalyst support applications. Presentado en: 15th Interamerican Microscopy Congress CIASEM - SAMIC; October 1–4, 2019, Buenos Aires, Argentina

Background The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 comparative risk assessment (CRA) is a comprehensive approach to risk factor quantification that offers a useful tool for synthesising evidence on risks and risk–outcome associations. With each annual GBD study, we update the GBD CRA to incorporate improved methods, new risks and risk–outcome pairs, and new data on risk exposure levels and risk–outcome associations. Methods We used the CRA framework developed for previous iterations of GBD to estimate levels and trends in exposure, attributable deaths, and attributable disability-adjusted life-years (DALYs), by age group, sex, year, and location for 84 behavioural, environmental and occupational, and metabolic risks or groups of risks from 1990 to 2017. This study included 476 risk–outcome pairs that met the GBD study criteria for convincing or probable evidence of causation. We extracted relative risk and exposure estimates from 46 749 randomised controlled trials, cohort studies, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. Using the counterfactual scenario of theoretical minimum risk exposure level (TMREL), we estimated the portion of deaths and DALYs that could be attributed to a given risk. We explored the relationship between development and risk exposure by modelling the relationship between the Socio-demographic Index (SDI) and risk-weighted exposure prevalence and estimated expected levels of exposure and risk-attributable burden by SDI. Finally, we explored temporal changes in risk-attributable DALYs by decomposing those changes into six main component drivers of change as follows: (1) population growth; (2) changes in population age structures; (3) changes in exposure to environmental and occupational risks; (4) changes in exposure to behavioural risks; (5) changes in exposure to metabolic risks; and (6) changes due to all other factors, approximated as the risk-deleted death and DALY rates, where the risk-deleted rate is the rate that would be observed had we reduced the exposure levels to the TMREL for all risk factors included in GBD 2017. Findings In 2017, 34·1 million (95% uncertainty interval [UI] 33·3–35·0) deaths and 1·21 billion (1·14–1·28) DALYs were attributable to GBD risk factors. Globally, 61·0% (59·6–62·4) of deaths and 48·3% (46·3–50·2) of DALYs were attributed to the GBD 2017 risk factors. When ranked by risk-attributable DALYs, high systolic blood pressure (SBP) was the leading risk factor, accounting for 10·4 million (9·39–11·5) deaths and 218 million (198–237) DALYs, followed by smoking (7·10 million [6·83–7·37] deaths and 182 million [173–193] DALYs), high fasting plasma glucose (6·53 million [5·23–8·23] deaths and 171 million [144–201] DALYs), high body-mass index (BMI; 4·72 million [2·99–6·70] deaths and 148 million [98·6–202] DALYs), and short gestation for birthweight (1·43 million [1·36–1·51] deaths and 139 million [131–147] DALYs). In total, risk-attributable DALYs declined by 4·9% (3·3–6·5) between 2007 and 2017. In the absence of demographic changes (ie, population growth and ageing), changes in risk exposure and risk-deleted DALYs would have led to a 23·5% decline in DALYs during that period. Conversely, in the absence of changes in risk exposure and risk-deleted DALYs, demographic changes would have led to an 18·6% increase in DALYs during that period. The ratios of observed risk exposure levels to exposure levels expected based on SDI (O/E ratios) increased globally for unsafe drinking water and household air pollution between 1990 and 2017. This result suggests that development is occurring more rapidly than are changes in the underlying risk structure in a population. Conversely, nearly universal declines in O/E ratios for smoking and alcohol use indicate that, for a given SDI, exposure to these risks is declining. In 2017, the leading Level 4 risk factor for age-standardised DALY rates was high SBP in four super-regions: central Europe, eastern Europe, and central Asia; north Africa and Middle East; south Asia; and southeast Asia, east Asia, and Oceania. The leading risk factor in the high-income super-region was smoking, in Latin America and Caribbean was high BMI, and in sub-Saharan Africa was unsafe sex. O/E ratios for unsafe sex in sub-Saharan Africa were notably high, and those for alcohol use in north Africa and the Middle East were notably low. Interpretation By quantifying levels and trends in exposures to risk factors and the resulting disease burden, this assessment offers insight into where past policy and programme efforts might have been successful and highlights current priorities for public health action. Decreases in behavioural, environmental, and occupational risks have largely offset the effects of population growth and ageing, in relation to trends in absolute burden. Conversely, the combination of increasing metabolic risks and population ageing will probably continue to drive the increasing trends in non-communicable diseases at the global level, which presents both a public health challenge and opportunity. We see considerable spatiotemporal heterogeneity in levels of risk exposure and risk-attributable burden. Although levels of development underlie some of this heterogeneity, O/E ratios show risks for which countries are overperforming or underperforming relative to their level of development. As such, these ratios provide a benchmarking tool to help to focus local decision making. Our findings reinforce the importance of both risk exposure monitoring and epidemiological research to assess causal connections between risks and health outcomes, and they highlight the usefulness of the GBD study in synthesising data to draw comprehensive and robust conclusions that help to inform good policy and strategic health planning. Copyright © 2018 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.

This work set out to explore the influence of kind and surface condition of carbon supports on the electrocatalytic activity of trimetallic PtRuCu alloy nanoparticles. The structure, composition, particle size and catalyst loading were determined by XRD, EDX, XPS, TEM and ICP-AES analysis. XRD studies revealed that support physical characteristics and surface conditions have an important influence in lattice strain, while XPS pointed out that a strong electronic interaction exists between the particles and the carbon support. Electrochemical experiments showed that the activated carbon black supported PtRuCu catalyst exhibits the best performance for methanol and ethanol oxidation and the lowest poisoning rate. The superior catalytic activity of this electrode can be rationalized in terms of metal-support interaction, Pt utilization efficiency and electrical conductivity of the carbon support. Furthermore, the as-prepared electrode exhibits 13 and 7 times higher activity towards methanol and ethanol oxidation when compared with a PtRu/C commercial catalyst. Fil: Comignani, Vanina. Universidad Nacional del Sur. Departamento de Ingeniería Química. Instituto de Ingeniería Electroquímica y Corrosión; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Sieben, Juan Manuel. Universidad Nacional del Sur. Departamento de Ingeniería Química. Instituto de Ingeniería Electroquímica y Corrosión; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Sanchez, Miguel Dario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentina Fil: Duarte, Marta María Elena. Universidad Nacional del Sur. Departamento de Ingeniería Química. Instituto de Ingeniería Electroquímica y Corrosión; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina

Low loaded Pd/α-Al 2 O 3 catalysts (

La incidencia de la estenosis de la arteria subclavia oscila entre el 3-4% en la poblacion general. Una diferencia de presion arterial de ? 10 mmHg entre ambas extremidades superiores sugiere el diagnostico. La angiografia es la prueba diagnostica definitiva y el control de los factores de riesgo cardiovascular es obligado. El abordaje quirurgico es el tratamiento de eleccion en pacientes sintomaticos. Describimos un caso de estenosis critica de la arteria subclavia izquierda, resuelta con angioplastia endovascular.

Resumen Los anticuerpos anticardiolipina (aCL) son anticuerpos de tipo antifosfolipido que reconocen especificamente los fosfolipidos que forman las membranas celulares. Pueden clasificarse como IgM/IgG/IgA dependiendo del isotipo involucrado o como dependientes/independientes de la β 2 glucoproteina I (GP1) dependiendo de si pueden ligarse a las cardiolipinas en presencia o en ausencia de β2GP1. Para su deteccion se emplea la tecnica ELISA de acuerdo con el estandar propuesto por Harris et al. Los aCL, junto con el anticoagulante lupico, son los marcadores mas utilizados para el diagnostico del sindrome antifosfolipido (SAF). Ademas de su presencia en el SAF primario, se encuentran en muchos otros entornos clinicos. Debemos recomendar a los pacientes que aun no han desarrollado trombosis evitar o controlar estrictamente otros factores de riesgo trombotico. En cuanto al tratamiento farmacologico, lo habitual es la antiagregacion plaquetaria con acido acetilsalicilico solo en los grupos de alto riesgo.

Resumen El factor reumatoide (FR) es un autoanticuerpo antiinmunoglobulina IgG, solicitado habitualmente en la investigacion de pacientes con problemas articulares. Su positividad serica posee una alta sensibilidad y especificidad para el diagnostico de la artritis reumatoide (AR) y, de hecho, forma parte de los criterios de clasificacion para AR, tanto de los de ACR de 1987 como de los nuevos criterios ACR/EULAR de 2010. Su deteccion en suero se considera un factor de mal pronostico, al asociarse con mayor frecuencia a manifestaciones extraarticulares. No obstante, su utilidad clinica y su interpretacion no estan bien establecidas, y podria llevar a un sobrediagnostico y a exponer al paciente a los efectos adversos de farmacos mal indicados. Ademas, el FR no es patognomonico de AR, ya que puede detectarse en otros procesos inflamatorios cronicos, asi como en enfermedades de origen infeccioso o tumoral e, incluso, en la poblacion general sana.

Antinuclear antibodies (ANA) are a diverse group of autoantibodies that bind macromolecular components of the cell nucleus. The presence of ANA in serum indicates the existence of an immunological response but not necessarily a disease. The discovery of positive ANA is common in many autoimmune diseases but also can occurs in healthy individuals (frequency increases with age), in diseases with other origin, with the use of some drugs, in tumours or in some infections. The medical request of ANA will be indicated in conditions where an autoimmune systemic disease is suspected. If we find ANA positive, more antibodies will be ordered according to the medical suspicion. Finally, it is important to remember that some autoimmune systemic diseases course with negative autoantibodies, so, the symptoms and the exclusion of other phenomenon are a key component for the diagnosis.

ResumenObjetivoEl objetivo del trabajo fue analizar, a partir de series temporales, las diferencias en la variabilidad de la marcha en dos situaciones distintas (marcha espontánea frente a marcha en tapiz rodante) en sujetos jóvenes, sanos y activos.MétodoLas series temporales de diez hombres sanos y físicamente activos fueron evaluadas en dos situaciones experimentales: a) 25 minutos caminando de forma espontánea por un circuito circular abierto; y b) 25 minutos caminando en un tapiz rodante a la misma velocidad que la situación a. Un dispositivo de captura fue diseñado expresamente para la obtención directa y almacenamiento de series de tiempo durante la marcha en ambas situaciones, a partir de un simple pulsador electrónico colocado en la zona del calcáneo de la palmilla del pie dominante introducida en la zapatilla deportiva. Se calcularon la media y desviación estándar (DE), la entropía aproximada (ApEn), la entropía muestral (SampEn) y la entropía multiescala (MSE).ResultadosLa DE, la ApEn y la SampEn no presentaron cambios significativos al comparar ambas situaciones experimentales. Todas las MSE disminuyen significativamente al comparar la marcha espontánea con la situación en tapiz.ConclusionesExiste una pérdida de complejidad de la señal cuando la marcha se realiza en un tapiz rodante y esto debe ser tenido en cuenta para futuras estudios en esta situación.AbstractObjectiveThe aim of study was to analyze the differences in gait variability (stride interval time series) in two different conditions (spontaneous walking vs. treadmill walking) in healthy and active young subjects.MethodThe stride interval time series derived from ten healthy and active males were studied in three experimental conditions: a) walking on level ground at their self-determined usual paces around open circle circuit for 25 minutes; and b) walking on a treadmill for 25 minutes at the same pace as in Situation a. A capture device enabled stride interval time series to be collected directly and stored during walking in both conditions, using a simple electronic push-button mounted in the heel of the dominant foot support of an insole placed in the running shoe. The mean and standard deviation (SD), Approximate Entropy (ApEn), Sample Entropy (SampEn) and Multiscale Entropy (MSE) were calculated.ResultsDE, ApEn and SampEn showed no significant changes between both experimental conditions. All MSE significantly decreased from the spontaneous walking to treadmill walking.ConclusionsThere was a loss of complexity signal when subjects walked on a treadmill. This should be taken into account for future studies under these conditions.

Resumen Desde la ultima mitad del siglo xx se ha producido un espectacular progreso en el conocimiento sobre el material genetico humano: se han caracterizado los cromosomas, se ha identificado la secuencia completa del genoma y se ha relacionado un gran numero de alteraciones de la estructura y secuencia del ADN con todo tipo de enfermedades, tanto hereditarias como no hereditarias (especialmente asociadas a cancer). Este desarrollo ha venido propiciado, y acompanado, por una gran cantidad de tecnicas para su estudio, muchas de las cuales se han trasladado a la investigacion y la caracterizacion de la carga genetica de los seres humanos, y a su aplicacion en la practica clinica para el diagnostico de ciertas patologias. Ello ha generado que, ademas de los estudios moleculares al nivel de identificacion de la mutacion de un gen, la citogenetica convencional se haya ampliado a la deteccion de alteraciones extremadamente pequenas de la estructura del cromosoma, dando lugar a una nueva area de diagnostico denominada citogenetica molecular. Esta incluye diversas tecnicas que detectan alteraciones pequenas en orden decreciente, desde las micro-deleciones y micro-duplicaciones detectables por sondas fluorescentes (FISH), hasta los arrays genomicos y los arrays basados en hibridacion genomica comparada (CGH) que detectan cambios aun mas pequenos. Sin embargo, debido a su alta resolucion, los arrays son capaces de identificar variaciones en el ADN cuyo significado, en muchos casos, es aun incierto. Esto implica que incluso algunas de las tecnicas que mas se estan utilizando en la actualidad, como la CGH array, precisen de una cuidadosa evaluacion antes de ofrecer un diagnostico.

We have studied carbon nanofibers (CNF) formed in the reforming reaction of CH4 with CO2 over a Pd (0, 42%)/α-Al2O3 catalyst at 973 K. The obtained nanostructured carbon material was characterized by high-resolution transmission electron microscopy (HRTEM). The results showed CNF of well-defined structures with diameters between 8 and 18 nm. A fraction of these fibers showed branched structures. Our results suggest that the fiber grows taking the metallic particle off the substrate, that the type of fiber obtained is related to the particle shape and that the origin of fiber growth is the formation of graphitic sheets on the metallic particle surface.

The preparation of different samples of vanadia supported on ultrastable zeolite ( VO x /USY ) is discussed. The samples were prepared in order to obtain highly dispersed V-species, avoiding the formation of crystalline vanadia and the destruction of the zeolite framework. Two methods were employed for preparing VO x /USY samples: an organic route using V(AcAc)3 and an inorganic route using NH4VO3. The characterization of the samples was performed with XRD, TPR, NH3-TPD, and N2 isotherms. From these results it is concluded that when VO x is supported on the surface of USY from acidic aqueous solution of ammonium metavanadate, the destruction of the zeolite framework is accomplished. For higher pH values in the impregnating solution, undesired V2O5 is formed on the USY surface. On the other hand, VO x /USY prepared from the organic precursor shows no destruction of the USY structure. In addition, highly dispersed VO x are formed, though for relatively high V loadings (6%) an obstruction of the zeolite windows takes place. The samples are tested as catalysts for gas phase dehydrogenation of n-butane to olefins. The catalysts prepared from NH4VO3 are almost inactive for the reaction. On the other hand, both samples prepared from V(AcAc)3 present initial conversion levels in the 8–12% range. However, the selectivity depends on the V loading, the catalysts with 6% loading being the most selective (75%). The catalytic patterns of the samples (activity and selectivity) are in agreement with the physicochemical features of the VO x /USY surface.

Resumen Introduccion El fallo hepatico agudo (FHA) es una entidad infrecuente pero con una alta mortalidad. La instauracion del trasplante hepatico, que es un tratamiento radical y de riesgo, ha mejorado el pronostico. No disponemos actualmente de criterios certeros que diferencien la posibilidad de regeneracion hepatica del FHA irreversible. El objetivo de nuestro estudio ha sido revisar las caracteristicas clinicas determinantes de la indicacion del trasplante y la evolucion de los pacientes con FHA en nuestro medio. Pacientes y metodo Estudio descriptivo retrospectivo de los casos de FHA ingresados en nuestra unidad en 3 anos. Resultados Se recogieron 11 casos. Se observo una menor mortalidad en los pacientes trasplantados (23%; 2 de 8) que en los no intervenidos (67%; 2 de 3). Un solo caso presento regeneracion hepatica. La mortalidad global fue del 36% con una mortalidad perioperatoria del 13%. Conclusion La indicacion de trasplante hepatico en los pacientes con criterios de mal pronostico en una fase temprana, con un bajo grado de encefalopatia y previo al desarrollo de fracaso multiorganico, podria mejorar el resultado del trasplante y disminuir la mortalidad perioperatoria.

Resumen Aunque la placenta membranacea y la placenta increta son entidades poco frecuentes, tienen una gran importancia pues habitualmente causan hemorragias abundantes y pueden conducir a una histerectomia. Suelen asociarse a placenta previa, antecedentes de cirugia uterina (cesarea, legrados) y gestaciones multiples, entre otras. Se comenta la posibilidad del diagnostico anteparto y diferentes modalidades de tratamiento

Introduccion La terapeutica endoscopica es una tecnica eficaz en el control de la hemorragia por ulcera peptica. Sin embargo, el sangrado persiste o recidiva hasta en el 10-30% de los enfermos. Las ulceras gastricas y duodenales presentan caracteristicas clinicas y endoscopicas diferentes, por lo que la eficacia del tratamiento endoscopico y los factores asociados a su fracaso deberian estudiarse por separado. Objetivos Analizar la eficacia de la terapeutica endoscopica en enfermos con alto riesgo de persistencia o recidiva del sangrado por ulcera gastrica y determinar los factores asociados al fracaso de esta tecnica. Pacientes y metodo Se trata de un estudio retrospectivo, basado en un protocolo de actuacion clinica, en el que se analizaron los 208 enfermos ingresados por hemorragia secundaria a ulcera gastrica con sangrado activo o estigmas de reciente sangrado, que recibieron terapeutica endoscopica, entre enero de 1992 y diciembre de 2001. Se recogieron variables clinicas, analiticas y endocopicas en el momento del ingreso, asi como el tratamiento medico y procedimiento endoscopico aplicado. La endoscopia se realizo dentro de las 12 h siguientes al ingreso. Los enfermos fueron clasificados en funcion de la respuesta al tratamiento endoscopico: a) pacientes con hemorragia limitada, y b) pacientes con persistencia o recidiva del sangrado por fracaso terapeutico. La pauta de actuacion en los enfermos con fallo del tratamiento endoscopico se realizo segun un protocolo previamente establecido. Las variables que obtuvieron significacion estadistica en el analisis univariante se incluyeron en un modelo de regresion logistica para identificar aquellas con un valor predictivo independiente para el fracaso de la terapeutica endoscopica. Resultados La hemostasia definitiva se logro tras la terapeutica inicial en 181 (87%) de los enfermos. La eficacia de una segunda terapia aumento el porcentaje de hemostasia a un 91% de los casos. En el modelo de regresion logistica, las unicas variables que se asociaron independientemente al fallo terapeutico inicial fueron: la repercusion hemodinamica en el momento del ingreso (p = 0,016; OR = 3,99), la necesidad de transfusion de hemoderivados previos a la endoscopia (p = 0,025; OR = 3,48), la localizacion alta de la ulcera gastrica (p = 0,050; OR = 3,08) y la terapeutica endoscopica no satisfactoria (p = 0,009; OR = 17,39). Conclusion Estas variables podrian identificar de forma temprana a un subgrupo de enfermos, lo que permitiria llevar a cabo una mayor vigilancia medico-quirurgica, asi como ofrecerles otras alternativas terapeuticas.

Resumen La amiloidosis por deposito de beta 2-microglobulina constituye una complicacion frecuente en los pacientes con insuficiencia renal cronica tratados con hemodialisis durante largos periodos de tiempo. Se caracteriza por una alta incidencia de afectacion poliarticular, desarrollando una espondiloartropatia destructiva que afecta predominantemente a la columna cervical, y que en casos graves puede provocar una subluxacion atlo-axoidea. Se presenta el caso clinico de un paciente varon de 54 anos de edad afectado de amiloidosis asociada a hemodialisis, que presento dolor cervical y rigidez resistente a tratamiento conservador. Tras realizar una radiografia lateral de columna cervical en maxima flexion y TAC cervical, se diagnostico una subluxacion atlo-axoidea anterior. El paciente fue intervenido quirurgicamente, estando actualmente asintomatico.